Rain Shaft/Shelf Cloud
PARTS OF A STORM
Anvil

INFLOW:
Rain-Free Base
Rain Free Base
-Forms from updraft which keeps all precipitation suspended
-If looking at the rain-free base, the wind should be at your back
-Look here for possible wall cloud development
SCUD
SCUD
-"Scattered Cumulus Under Deck"
-These are very low level clouds below the rain-free base
-Often confused as funnel clouds
-Lack rotation and are disconnected with main cloud base
Wall Cloud
Wall Cloud
-Lowering from the rain-free base
-Occur due to influx of moist air which lowers the dewpoint depression, and in turn, the cloud base (LCL).
-"Most tornadoes form from wall clouds, but most wall clouds don't form tornadoes"
-Look for rotation as a good precursor to possible tornado formation.
Funnel Cloud
Funnel Cloud
-Funnel clouds can extend downward from a rotating wall cloud.
-Violently rotating column of air extending from the base of a thunderstorm as a condensation funnel.
-NOT in contact with the ground.
-Watch as funnel extends to ground or debris cloud forms which would make it a tornado.
Tornado
Tornado
-Violently rotating column of air extending from the base of a thunderstorm in contact with the ground.
-Look for debris cloud or condensation funnel extending from wall cloud to the ground.
-Strength based on Enhanced Fujita Scale (damaged based scale).
-Tornadoes should be reported to the local weather service office or by dialing 911.
-Extreme caution should be used when observing tornadoes (they can move at very fast speeds and change directions quickly)

OUTFLOW:
Shelf Cloud
Shelf Cloud
-Shelf clouds usually represent the leading edge of the gust fronts
-Very fast straight-line winds associated with shelf cloud
-Identifiable as long, skinny cloud lowered from the main base of the storm
-Differentiated from wall clouds because when looking at a shelf cloud, wind will be in your face.

Hail Shaft
Hail Shaft
-Differentiated from rain shafts by their off-white/greyish coloration.
-Large hail (up to the size of softballs) common in the Great Plains.
-Largest hail often on the updraft/downdraft border.
-While chasing, hail shafts should be avoided (can hide deadly tornadoes, dent cars, and destroy windshields).
Rain Shaft
Rain Shaft
-Rain shafts have a dark grey/bluish tint as opposed to hail shafts.
-The danger in rain shafts come from the flooding potential ("Turn around don't drown") and their shielding visibility of potentially more dangerous parts of a storm.

Gustnado
Gustnado
-Gustnadoes are not technically tornadoes because they are not in contact with the main cloud base.
-Gustnadoes are weaker than most wall cloud based tornadoes but can still cause minor damage (especially to cars).
-Gustnadoes can be easily differentiated from tornadoes because they occur in teh outflow part of a storm; often under the shelf cloud. 

OTHER CLOUD FEATURES:
Mammatus Clouds
Mammatus Clouds
-Mammatus clouds form from the sinking of moist air into drier air.
-Think of them as an upside down cloud.
-Not necessarily structurally significant but often provide breathtaking sights and pictures.
Towering Cumulus Clouds
Towering Cumulus
-Cumulus clouds with significant vertical development.
-Often aller than they are wide.
-Good sign of instability and potential storm development
-Become Cumulonimbus clouds when rain begins to fall.
-Can form in lines along fronts or as isolated clouds (these are often the ones to chase as they will solely use all of the available moisture and energy)
Anvil
Anvil
-Gets name from the anvil shape (larger on top than on the bottom).
-Represents teh top of a thunderstorm.
-Not all storms possess anvil clouds.
-Can be seen from over 50 miles away if terrain permits.
-Tops of anvils often 40,000 feet high. 

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